... history of IS–LM Keynesianism,9 the Post Keynesian response and Keynes s analysis of the investment decision (a crucial aspect of Keynes s theory, as he saw investment as the motor driving the level... University of Cambridge Social Theory is experiencing something of a revival within economics Critical analyses of the particular nature of the subject matter of social studies and of the types of method,.. .The Philosophy of Keynes s Economics John Maynard Keynes was arguably the most influential Western economist of the twentieth century His emphasis on the nature and role of uncertainty in economics